1. Field of the Invention
The present invention relates to a method of manufacturing an extruded, smooth finished solid sheet or film of thickness &lt;1 mm, comprised of a thermoplastic having a glass transition temperature &gt;50.degree. C., by extruding the plastic in a thermoplastic state through a slot nozzle to form a flat extruded strip, and smoothing the surfaces of the strip. The term "solid" here indicates that the extruded and smoothed strip (sheet or film) has no internal voids; hereinafter, for simplicity, the terms "sheet" and "film" will indicate corresponding strips which are solid.